Timothy N. Showalter, MD, MPH

As part of a special course on brachytherapy for prostate cancer from the American Brachytherapy Society (ABS) and Grand Rounds in Urology, Timothy N. Showalter, MD, MPH, Associate Professor of Radiation Oncology at the University of Virginia in Charlottesville, discusses long-term outcomes of and recent advances in brachytherapy monotherapy for low-risk (LR), favorable intermediate-risk (fIR), and selected unfavorable intermediate-risk (uIR) prostate cancer. He begins by listing potential advantages of brachytherapy monotherapy, highlighting that it features a single episode of care, is cost-effective, is multidisciplinary, has excellent long-term outcomes, features established technology to support tailored dosimetry and quality, and has been the subject of recent advances that enhance implant quality and reduce toxicity. Dr. Showalter then considers patient selection for brachytherapy monotherapy, noting that MRI may be useful in selecting patients with LR, fIR, and selected uIR disease. He emphasizes the importance of assessing whether a patient’s anatomy is suitable for implant based on gland size and arch interference, as well as the need to determine whether a patient has adequate baseline urinary function. Dr. Showalter also lists contraindications to brachytherapy monotherapy, including relative contraindications such as a large TURP defect, a large gland, and a large median lobe, as well as absolute contraindications such as inability to tolerate anesthesia, unacceptable operative risk, and the absence of a rectum. He then moves on to consider long-term outcomes of brachytherapy monotherapy, noting that for LR, fIR and selected uIR, follow-up data indicates biochemical progression-free survival of greater than 90%. Dr. Showalter also observes that outcomes are favorable in terms of toxicity, although there are some declines in urinary and sexual function. Finally, Dr. Showalter briefly summarizes recent advances in brachytherapy, emphasizing the role of advanced imaging such as MRI in helping to tailor brachytherapy dose and increase the personalization of care.